"All have sinned and fall short of the glory of god". Is this justification enough for genocide for the Bible "God"?

No it's a twisted line of reasoning. The god of the Bible supposed to be forgiving but it's exactly the opposite

So are you just going to ignore all the genocide god commits in the bible? That's not very loving or forgiving to me

This verse is not meant as a justification. You apparently have trouble with language.

1 John 1:8 If we make the statement: " We have no sin, we are misleading ourselves and the truth is not in us. We are all sinners, but through the undesevered love and goodness of God and the love and willingness of his son to die that we might be forgiven for our sins, we live. We can repent, turn our lives around and bring our lives in harmony with God's purpose. If God was so cruel he would just allow us all to die in sin and not give us the chance to be obedient to him, proving that even though imperfect, we still can put forth the effort and willingness to serve God faithfully. He will rewards those who choose to do so with everlasting life in perfection, which has always been his purpose for humans. It's up to you to believe it or not. God will not force anyone to make the choice.

Jehovah God is not accountable to humans, therefore, if he deems one wicked he has the Divine Right to take their gift of life away forever-Psalms 37:10.

It could be. It's up to Him.

You don't have any ground on which to judge God.

It was to him.

The Bible says that “all have sinned and fall short of the glory of God.” (Romans 3:23; 1 Kings 8:46; Ecclesiastes 7:20; 1 John 1:8) Why is that so?

The first humans, Adam and Eve, were sinless in the beginning. That is because they were created perfect, in God’s image. (Genesis 1:27) However, they lost their perfection by disobeying God. (Genesis 3:5, 6, 17-19) When they had children, they passed on sin and imperfection as inherited defects. (Romans 5:12) As King David of Israel said, “I was born guilty of error.”—Psalm 51:5.

The Bible "God" has killed no one, and never will.

His creation,his will. Repent now for God ,the father will not be mocked. Your time will come.